• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.7
• /
• pp.1581-1587
• /
• 2004

In this paper, We have proposed an Heterodyne technique to generate millimeter-wave signal. Microwave signals in cellular broadband mobile communication networks and distributed networks can favorably be generated and distributed by optical techniques. In principle, these techniques have already been investigated for optical control of phase-array antennas, characterization of photo-detector and phase locking of millimeter-wave oscillators and now being applied to wireless communications. The generation and transmission of millimeter-wave radio signals by optical means is of interest for future pico-cell broadband mobile communication system, especially for systems operating at frequencies of 300Hz.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.6
• /
• pp.1223-1228
• /
• 2018

LTE-R(Long Term Evolution - Railway), as a mobile communication technology to support safety operation of train on high speed railway system, have to be equipped appropriately by hand-over method for high moving environment of train. In this paper, hand-over performance of LTE-R network, which is used in railway communication system, is analyzed and hand-over implementation condition is suggested with this analysis. The performance analysis of this study is carried out with computer simulation with NS(Network Simulator)-3. SINR(Signal to Interference and Noise Ratio) and RSRP(Reference Signal Received Power), and Data Rate is used for hand-over performance parameter.

• Journal of Satellite, Information and Communications
• /
• v.6 no.1
• /
• pp.6-11
• /
• 2011

In this paper presents a new approach to evaluate reliability indices of electric distribution systems using genetic Algorithm (GA). The use of reliability evaluation is an important aspect of distribution system planning and operation to adjust the reliability level of each area. In this paper, the reliability model is based on the optimal load transferring problem to minimize load generated load point outage in each sub-section. This approach is one of the most difficult procedures and become combination problems. A new approach using GA was developed for this problem. GA is a general purpose optimization technique based on principles inspired from the biological evolution using metaphors of mechanisms such as natural selection, genetic recombination and survival of the fittest. Test results for the model system with 24 nodes 29 branches are reported in the paper.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.7 no.5
• /
• pp.1245-1251
• /
• 2012

Recently, needs of recreational marine industry are consistently increasing due to increasing of income and pursuit on well-being. For these needs, central government and local governments have tried to build tens of marinas to meet demands and promote related industries. Therefore, need of smart pedestal system has also increased. However, domestic companies have not manufactured smart pedestal systems, so many pedestal systems have been imported from advanced countries such as England, Denmark, and Italy. This research has developed a smart pedestal system using IT convergence technology. This system is assembled by each several module which has its own function and board. Each module is not developed on an embedded OS. Instead, it has its customized operational software based on its kernel. Thus, this system brings about cost reduction of productions and maintenance.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.4
• /
• pp.819-825
• /
• 2003

The purpose of this study is to develop the speaker recognition system which can select one of operating modes in FES for general paralysis patients. As spiral injury by traffic accident, industrial disaster, or stroke has been increased, the development of FES(Functional Electrical Stimulator) system is urgent to prevent paralysis and atrophy, and to assist the patients walking. For these patients we developed FES system(1). To operate this system one of several operating modes must be selected. As this can not be done by general paralysis patients, an attempt has been tried in this study to select the mode by speaker recognition system. RSC-300 of sensory co. has been chosen as a speaker recognition chip, and PIC16F84 is adapted to interface RSC-300 and FES system.

• Proceedings of the KAIS Fall Conference
• /
• 2009.12a
• /
• pp.837-841
• /
• 2009

언제, 어디서나 컴퓨터 사용과 통신이 가능한 유비쿼터스 환경의 구축과 개발은 부존자원이 부족한우리나라의 산업 전략에 부합하며 현재 우리나라가 보유한 정보통신 관련기술의 우위를 바탕으로 성장할 가능성이 큰 분야로써 정부가 미래의 10대 성장 동력으로 선정한 분야의 한가지 이다. 배전시스템에서의 이 분야 기술 개발의 핵심내용은 유비쿼터스 기술을 활용한 고 신뢰도의 배전계통 운용 및 높은 수준의 전기품질 관리체제 구축 그리고 이를 통한 관련 산업 즉, 전력거래, 전력시장 유지 및 운영을 위한 핵심 세부 콘텐츠와 부가서비스의 창출을 위한 기반 인프라의 개발 및 구축에 있는데, 이 기반기술의 중심에 배전시스템이 있으므로 이를 고 신뢰, 고품질 기반의 시스템으로 지능화하는 것이 필요하다. 따라서 본 논문에서는 태양광, 풍력 등의 분산전원이 계통에 연계되는 장래의 스마트배전시스템에 대하여, 기존의 배전계통의 전압조정방안과 비교, 분석하여 기술적인 적합여부를 종합적으로 평가하고자 한다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.4
• /
• pp.737-746
• /
• 2009

In this study, we have developed one chip system IC for preventing the overload, detecting an abnormal conditions, and controlling the fire prevention in the intelligent home appliances. For the purpose, a circuit detectable an electric leak for preventing an electric shock, and a circuit detectable arc that has effect directly on the fire are designed. The circuits designed on every block are verified by comparing simulation with bread-boarding using a standard transistors. The system IC is fabricated by using 34 V 2 metal $1.5{\mu}m$ bipolar transistor process from evaluation results. The electrical performances of IC application circuits and the system IC equipped on PCB board are evaluated. It is confirmed that the system IC is well operated for arc and ground fault(GF) signal.

• Electronics and Telecommunications Trends
• /
• v.27 no.1
• /
• pp.1-18
• /
• 2012

미래 사회는 나노기술(NT)을 바탕으로 IT-ET-BT 기술이 융합된 유비쿼터스 사회로 진화하고 있으며, 미래 산업 사회로의 전환을 위해서는 성능개선이 아닌 성능한계 돌파의 패러다임 전환이 가능한 임계성능의 나노 소재/신소자의 개발이 절실히 요구되고 있다. 또한 차세대 단말기는 휴대성의 편리함, 융복합화/다기능화, 인간 친화형이 요구되고, flexible/stretchable/bendable한 형태로 발전하고 있는 상황이다. 나노 피에조트로닉스(nanopiezotronics) 기술은 역학적 에너지를 전기적 에너지로 변환하는 나노 발전 소자(nanogenerator)의 원리를 기반으로 하며 나노선, 나노벨트와 같은 1차원적 나노구조 소재의 압전성과 반전도성이 결합된 특성을 이용한 신기능의 미래 IT 융합 나노 전자/에너지 소자를 구현하는 기술로서 미래 유망 기술로 부각되고 있다. 현재 기술 수준은 압전 전계 효과 트랜지스터, 압전-다이오드, 압전 센서, 압전 나노 발전 소자 등과 같은 prototype 소자를 제작하는 수준에 머무르고 있으나 향후 초고감도 압전 센서, 자가발전 MEMS/NEMS 및 나노 시스템, 스마트 웨어러블 시스템, 건강 모니터링 시스템, 인체 삽입형 소자, portable 및 투명 유연 전자소자 등의 다양한 미래 융합 나노 소자 및 시스템에 광범위한 활용이 가능하며, 향후 신기능의 소자/부품/시스템 창출을 위한 기술로 자리매김할 것으로 전망된다. 본고에서는 압전 나노선, 나노튜브, 나노섬유 등의 1차원적 나노구조체 기반의 nanopiezotronics 기술과 최근의 연구결과들을 소개한다.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.10
• /
• pp.935-940
• /
• 2016

Recently, wireless power transmission system is gradually extended to technology in various fields such as lighting field, electric vehicles and smartphones wireless charging system. The largest of the two elements for high transmission efficiency of the wireless power transmission system are resonant coils and power amplifiers. In this paper, in order to build a high efficient wireless power transmission system, we introduce the resonance coil manufacturing method and high efficiency power amplifier design method that operates at 6.78MHz.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.2
• /
• pp.443-448
• /
• 2018

Recently, Hybrid Electric Vehicle(: HEV) is in the spotlight to global warming caused by carbon dioxide and emission reduction. HEV consists of a combination of mechanical engine and electric motor system. The flow of energy required to drive a HEV depends on the driving conditions of the vehicle. In this paper, we study the contents of HEV education using real-time monitoring system. A real-time monitoring system consisting of hardware and virtual programs is used to simulate the overall operation of a HEV through simulations according to driving conditions and to explain how to learn through hardware.